A birth chart (also called a natal chart) is a map of where the planets and key astronomical points were in the zodiac, relative to Earth, at the date, time, and place you were born. It is not a single “sign” summary like a newspaper Sun-sign horoscope—it is a full wheel of positions that astrologers use to talk about temperament, timing, and life themes.

Your Sun sign is only one ingredient. Most people know it from their birth month range. A full chart adds your Moon sign, Rising (Ascendant) sign, the twelve houses (life areas), and aspects between planets. Two people with the same Sun sign can still have very different charts if their Moon, Rising, or house positions differ.

That is why our calculator asks for an exact place from search and lets you mark time unknown when needed. We still compute a chart, but you should treat Rising and house detail as approximate without a reliable birth time.

Astraia’s free tool produces a Western tropical natal chart: Sun, Moon, Rising when supported by your data, house placements in the on-page summary, and a chart wheel in the browser when available. You can also request an optional PDF interpretation by email—no account is required to generate the chart itself.